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BMS 18N850 4 Ohms

18" · 4 Ω · 1200 W · 97.8 dB · datasheet ↗

Thiele-Small parameters

Nominal size18"
Impedance4 Ω
Fs23.7 Hz
Qts0.261
Qes0.27
Qms7.45
Vas288 L
Sd1212 cm²
Xmax11 mm
Re3 Ω
Bl23.1 T·m
Mms322.4 g
Pe1200 W
Sensitivity97.8 dB

Alignment hint

EBP88 · flexible
Sealed Vb (Qtc ≈ 0.71)≈ 45.4 L

EBP 50-100: works in either a sealed or ported alignment.

Rules of thumb from T/S parameters only. Verify against a real simulation before cutting wood.

Substitute candidates

DriverFs (Hz)QtsVas (L)Xmax (mm)Sens (dB)FitNotesCompare
BMS 18N850 8 Ohms24.4 +0.70.251 -0.01288 =10.6 -0.495.5 -2.3close8 Ω vs 4 Ω: amp load changes · Xmax 10.6 mm < 11 mm: lower excursion-limited SPL+
Oberton 18NSW70030.48 +6.780.243 -0.02309.02 +21.0214 +397.5 -0.3usable8 Ω vs 4 Ω: amp load changes · 700 W vs 1200 W: lower power handling+
RCF LF 18X40130 +6.30.298 +0.04274 -1411.4 +0.497.5 -0.3usable8 Ω vs 4 Ω: amp load changes+
RCF LF18X40130 +6.30.3 +0.04274 -1412 +197.5 -0.3usable8 Ω vs 4 Ω: amp load changes+
RCF LF18Y40230 +6.30.3 +0.04274 -1412 +197.5 -0.3usable8 Ω vs 4 Ω: amp load changes+
RCF LF18X40028 +4.30.27 +0.01340 +529 -297.5 -0.3usable8 Ω vs 4 Ω: amp load changes · Xmax 9 mm < 11 mm: lower excursion-limited SPL+
Faital PRO 18XL200028 +4.30.27 +0.01232.1 -55.916.32 +5.3297 -0.8usable8 Ω vs 4 Ω: amp load changes+
18 Sound 18NLW940033 +9.30.26 =268 -209.5 -1.598 +0.2usable8 Ω vs 4 Ω: amp load changes · Xmax 9.5 mm < 11 mm: lower excursion-limited SPL+
BMS 18N840V228.5 +4.80.314 +0.05288 =10 -197.1 -0.7usable8 Ω vs 4 Ω: amp load changes · Xmax 10 mm < 11 mm: lower excursion-limited SPL+
RCF LF 18X400 v228 +4.30.278 +0.02340 +529 -298 +0.2usable8 Ω vs 4 Ω: amp load changes · Xmax 9 mm < 11 mm: lower excursion-limited SPL+

Compare the closest 3 against the 18N850 4 Ohms →

Ranked on parameter similarity only (Qts, Fs, Vas, Xmax, sensitivity). Same nominal size required. A hint, not a simulation, model the swap before cutting or buying.

Used in enclosures (0)

No enclosure in the catalog uses this driver yet.